The racial gap in cognitive impairment and dementia has emerged as a serious public health problem. Researchers using nationally representative data estimated that among those aged 71 years and older Blacks were approximately two times more likely to have dementia than Whites. Blacks also had four times greater risk of having mild cognitive impairment than Whites. The epidemic of cognitive impairment and dementia among older Blacks will worsen in future years as the number of Blacks aged 65 and over will more than double by 2030, increasing from 2.8 million in 2000 to 7.2 million by 2030. Despite developments in understanding the risk factors associated with cognitive impairment and dementia in recent years, very few population-based studies have investigated the origins, mechanisms, and consequences of the racial gap in cognitive impairment. The proposed investigation will carefully define the magnitude of the gap in cognitive impairment, the proximal and distal factors associated with the gap, and the consequences of the gap for cognitive-impairment-free life expectancy for older Blacks and Whites. Data come from the Health and Retirement Study (HRS), an ongoing nationally representative, longitudinal survey of Americans 51 years of age and older and Aging, Demographics, and Memory Study (ADAMS). ADAMS is part of the HRS in that a subset of HRS respondents aged 70 years and older were clinically assessed and assigned a diagnosis of dementia, cognitive impairment but not demented (CIND), or normal cognition. Specifically, we aim to 1) examine the sensitivity and specificity of the HRS cognitive functioning measures as a screening tool for cognitive impairment and dementia for Blacks and Whites respectively; 2) examine life course pathways associated with the racial gap in cognitive impairment; 3) estimate life expectancy with and without cognitive impairment for Blacks and Whites by gender and childhood conditions. The analysis will be based on the 1998-2008 waves of HRS. Models of both prevalence and incidence of cognitive impairment will be estimated for persons aged 70 years and older. The findings from this research will advance our understandings of the origins, mechanisms, and consequences of racial gaps in cognitive impairment and can help policy makers and public health professionals design effective interventions to reduce racial disparities in cognitive impairment and make plans for the associated health care and long-term care needs of those suffering from cognitive impairment.